Novel Ultrastructural Insights into the Clear-Cell Carcinoma of the Pancreas: A Case Report.

Pancreatic cancer, most frequently as ductal adenocarcinoma (PDAC), is the third leading cause of cancer death. Clear-cell primary adenocarcinoma of the pancreas (CCCP) is a rare, aggressive, still poorly characterized subtype of PDAC. We report here a case of a 65-year-old male presenting with pancreatic neoplasia. A histochemical examination of the tumor showed large cells with clear and abundant intracytoplasmic vacuoles. The clear-cell foamy appearance was not related to the hyperproduction of mucins. Ultrastructural characterization with transmission electron microscopy revealed the massive presence of mitochondria in the clear-cell cytoplasm. The mitochondria showed disordered cristae and various degrees of loss of structural integrity. Immunohistochemistry staining for NADH dehydrogenase [ubiquinone] 1 alpha subcomplex, 4-like 2 (NDUFA4L2) proved specifically negative for the clear-cell tumor. Our ultrastructural and molecular data indicate that the clear-cell nature in CCCP is linked to the accumulation of disrupted mitochondria. We propose that this may impact on the origin and progression of this PDAC subtype.

Case of metastatic clear cell odontogenic carcinoma with response to chemoimmunotherapy.

Our patient initially presented with 6 months of left jaw pain and gingival bleeding, leading to the discovery of a radiolucent left maxillary mass on dental evaluation. A biopsy confirmed clear cell odontogenic carcinoma, and the patient was treated with definitive surgery and radiation for localised disease. Unfortunately, the patient was found to have pulmonary metastases 3 months after initial management and was subsequently treated with a combination of cytotoxic chemotherapy and immunotherapy with a partial response. To our knowledge, this is the first case demonstrating the successful use of chemoimmunotherapy in metastatic clear cell odontogenic carcinoma.

PURE vs. mixed clear cell ovarian carcinomas: Is there any impact on survival?

OBJECTIVE: Our primary aim in this study is to define the clinical characteristics of patients with clear-cell ovarian carcinoma and evaluate the prognostic factors affecting survival. STUDY DESIGN: Records of 85 patients, operated between 2000 and 2018, for an adnexal mass and whose final pathology reported clear cell ovarian carcinoma were reviewed. The study considered demographic data, clinical characteristics of the patients, as well as pure and mixed-type clear cell histology. The patients' follow-up time, disease-free and overall survival recorded. The primary outcomes were disease-free survival (DFS) and overall survival (OS). RESULTS: The median age of the patients at diagnosis was 52. In 64.7 % of the cases, clear cell histology was pure, while the others (35.3 %) were mixed. Patients with ovarian endometriosis constituted 27.1 % of the whole population. The median OS for the entire population was 92 months (95 %CI:72-124). On univariate and multivariate analyses, advanced age was found to have a significant independent impact on OS and DFS (p < 0.05) and, was associated with a worse prognosis. Also, the multivariate analyses showed that the presence of endometriosis has a significant independent impact on OS (p < 0.05). When examining the relationship between the histological origin (mixed vs. pure) and 5-year survival, the mixed type showed longer OS and DFS rates (76.8 % vs. 69.8 %, 61.5 % vs. 53.8 %), the difference was not statistically significant (p > 0.05). CONCLUSION: This retrospective study showed that although mixed type histological origin was associated with higher OS and DFS rates compared to pure type in patients with CCOC, the difference was not statistically significant. Advanced age and the presence of endometriosis was found to have a significant independent effect on OS and DFS and was associated with a worse prognosis. Overall, this study provides useful insights into the clinical characteristics of patients with CCOC and identifies important prognostic factors affecting survival.

Cervical clear cell carcinoma: Case report and literature review.

RATIONALE: Clear cell carcinoma (CCC) is a highly invasive malignant tumor. CCCs of the female reproductive system occur mostly in the endometrium and ovaries and rarely in the cervix. So, it is difficult to diagnose cervical clear cell carcinoma (CCAC) on imaging. This report helps to further deepen our understanding of CCAC. PATIENT CONCERNS: A 39-year-old female patient presented with vaginal discharge with no obvious cause, elevated levels of carcinoembryonic antigen (CEA), CA125, CA153, and squamous cell carcinoma antigen (SCC), and underwent ultrasonography (US) CT and MRI examination in our hospital, which showed a mass in the cervix of the uterus, considered of cervical squamous carcinoma. DIAGNOSES: The cervix biopsy guided by vaginoscope biopsy and immunohistochemistry confirmed CCAC, combined Magnetic Resonance Imaging examination, CCAC with pelvic lymph node metastasis was considered. INTERVENTIONS AND OUTCOMES: The patient refused further treatment and was discharged from hospital. LESSONS: CCAC exhibited no specific symptoms, and is slightly different from cervical squamous carcinoma in image features, mainly relying on immunohistochemistry for diagnosis. The reported case raised awareness of CCAC.

Differentiation of ovarian serous carcinoma from ovarian clear cell carcinoma using a 10-gene signature selected by comprehensive gene expression analysis.

AIM: Ovarian serous carcinoma (OSC) and ovarian clear cell carcinoma (OCCC) are two major histological types of epithelial ovarian carcinoma (EOC), each with different biological features and clinical behaviors. Although immunostaining is commonly used for differential diagnosis between OSC and OCCC, correct identification of EOC with mixed-type histology is sometimes a diagnostic challenge. The aim of the present study was to explore candidate genes as potential diagnostic biomarkers that distinguish OSC from OCCC. METHODS: A total of 57 surgical specimens were obtained from EOC patients who had previously undergone primary debulking surgery. Total RNAs were extracted from fresh-frozen tissues of EOC patients, and were used for comprehensive gene expression analysis using DNA microarray technology. RESULTS: Ten candidate genes, FXYD2, TMEM101, GABARAPL1, ARG2, GLRX, RBPMS, GDF15, PPP1R3B, TOB1, and GSTM3 were up-regulated in OCCC compared to OSC. All EOC patients were divided into two groups according to hierarchical clustering using a 10-gene signature. CONCLUSION: Our data suggest that the 10 candidate genes would be an excellent marker for distinguishing OSC from OCCC. Furthermore, the molecular signatures of the 10 genes may enlighten us on the differences in carcinogenesis, and provide a theoretical basis for OCCC's resistance to chemotherapy in the future.

Pulmonary salivary gland tumor-hyalinizing clear cell carcinoma: a literature review.

Primary pulmonary hyalinizing clear cell carcinoma (HCCC) is a very rare lung tumor that accounts for less than 0.09% of all primary lung tumors and has no specific epidemiology. The correct diagnosis requires imaging, laboratory, pathological, immunohistochemical, and molecular examination. The most typical feature of pulmonary HCCC is the clear cell component with clear stroma. In addition, the fusion gene EWSR1::ATF1 due to t(12;22)(q13;q12) is essential for the pathological diagnosis of pulmonary HCCC. The main treatment for pulmonary HCCC is surgery. This review focus on the pathological features, immunohistochemical examination, mutation analysis and treatment of pulmonary HCCC.

The impact of lymphadenectomy on ovarian clear cell carcinoma: a systematic review and meta-analysis.

BACKGROUND: Ovarian clear cell carcinoma (OCCC) shares treatment strategies with epithelial ovarian cancer (EOC). Due to OCCC's rarity, there's a lack of prospective studies on its surgery, resulting in heterogeneous and limited existing data. This study aims to clarify the prognostic significance of lymphadenectomy in OCCC patients. METHODS: We systematically searched Web of Science, Scopus, PubMed, and Google Scholar until July 2023 for studies investigating lymphadenectomy's effects on OCCC patients. We calculated pooled hazard ratios (HR) with 95% confidence intervals (CI). This study is registered in PROSPERO (CRD42021270460). RESULTS: Among 444 screened articles, seven studies (2883 women) met inclusion criteria. Our analysis revealed that lymphadenectomy significantly improved disease-specific survival (DSS) (HR = 0.76, 95%CI = 0.60-0.95, P = 0.02) and disease-free survival (DFS) (HR = 0.58, 95%CI = 0.34-0.99, P = 0.05). However, it did not significantly affect overall survival (OS) (HR = 0.80, 95%CI = 0.60-1.06, P = 0.12) or progression-free survival (PFS) (HR = 0.95, 95%CI = 0.64-1.42, P = 0.79). Notably, some earlier studies reported no survival benefit, warranting cautious interpretation. CONCLUSION: Lymphadenectomy does not significantly enhance OS and PFS for OCCC but does improve DFS and DSS. Tailoring treatment to individual patient profiles is imperative for optimal outcomes. Precise preoperative or intraoperative lymph node metastasis detection is essential for identifying candidates benefiting from lymphadenectomy. Collaborative international efforts and an OCCC database are pivotal for refining future treatment strategies.

Hyalinizing Clear Cell Carcinoma in the Sphenoid Sinus.

ABSTRACT: A 39-year-old man presented with a 1-month history of headaches. Imaging revealed a mass with extensive destruction. T2-weighted imaging displayed mixture of low and sponge-like high intensities and also dark area, with FDG PET/CT showing uneven but intense accumulation. Biopsy confirmed EWSR1 rearrangement, and hyalinizing clear cell carcinoma (HCCC) was diagnosed. HCCC, recently renamed from clear cell carcinoma in the fifth edition of the World Health Organization Classification of Head and Neck Tumors, is a rare tumor. This case describes the features of T2-weighted imaging and FDG PET patterns in HCCC, possibly contributing to their consideration in the differential diagnosis.

Practice patterns, time trends and quality of care of uterine cancer in Belgium: An analysis of the EFFECT database.

OBJECTIVES: To investigate the practice patterns and quality of care for uterine cancer on a national level in Belgium, including trends in practice over the period 2012-2016. METHODS: Quality indicators were measured using the EFFectiveness of Endometrial Cancer Treatment (EFFECT) database. Multivariable logistic mixed regression was used to test for associations between the quality indicators and year of diagnosis, adjusted for potential confounders and intra-cluster correlations. RESULTS: The EFFECT database includes 4178 patients diagnosed with uterine cancer in the period 2012-2016. Minimally invasive surgery (laparoscopic or robotic-assisted) was applied in 61.6% of patients who had surgery for clinical stage I endometrial carcinoma (EC), increasing from 52.9% in 2012 to 66.4% in 2016. At least pelvic lymph node staging was performed in 69.0% of patients with clinical stage I, high-grade EC; and in 63.9% of patients with clinical stage I-II serous carcinoma, clear cell carcinoma or carcinosarcoma. The latter increased from 48.8% in 2012 to 77.2% in 2016. Adjuvant radiotherapy (external beam and/or brachytherapy) was offered to 33.5% of patients who had surgery without lymph node staging for pathological stage I EC at high-intermediate or high risk of recurrence. Adjuvant chemotherapy was administered to 64.4% of patients with pathological stage III-IVA EC. CONCLUSIONS: Study results indicate an overall good quality of care for patients with uterine cancer in Belgium. Treatment areas with potential room for improvement include the use of minimally invasive surgery, comprehensive surgical staging and adjuvant therapy, which confirms the remaining controversies in uterine cancer treatment and the need for further research.

Clear Cell Adenocarcinoma of Urethra: Clinical and Pathologic Implications and Characterization of Molecular Aberrations.

PURPOSE: This study aimed to evaluate the molecular features of clear cell adenocarcinoma (CCA) of the urinary tract and investigate its pathogenic pathways and possible actionable targets. MATERIALS AND METHODS: We retrospectively collected the data of patients with CCA between January 1999 and December 2016; the data were independently reviewed by two pathologists. We selected five cases of urinary CCA, based on the clinicopathological features. We analyzed these five cases by whole exome sequencing (WES) and subsequent bioinformatics analyses to determine the mutational spectrum and possible pathogenic pathways. RESULTS: All patients were female with a median age of 62 years. All tumors were located in the urethra and showed aggressive behavior with disease progression. WES revealed several genetic alterations, including driver gene mutations (AMER1, ARID1A, CHD4, KMT2D, KRAS, PBRM1, and PIK3R1) and mutations in other important genes with tumor-suppressive and oncogenic roles (CSMD3, KEAP1, SMARCA4, and CACNA1D). We suggest putative pathogenic pathways (chromatin remodeling pathway, mitogen-activated protein kinase signaling pathway, phosphoinositide 3-kinase/AKT/mammalian target of rapamycin pathway, and Wnt/ß-catenin pathway) as candidates for targeted therapies. CONCLUSION: Our findings shed light on the molecular background of this extremely rare tumor with poor prognosis and can help improve treatment options.

Immunohistochemical Analysis of the Tissue Factor Pathway Inhibitor-2 in Endometrial Clear Cell Carcinoma: A Single-center Retrospective Study.

The tissue factor pathway inhibitor-2 (TFPI2) was recently identified as a diagnostic serum marker for ovarian clear cell carcinoma. Moreover, the immunohistochemical expression of TFPI2 in ovarian clear cell carcinoma was recently reported. This single-center retrospective study aimed to evaluate whether TFPI2 can be a specific biomarker for immunohistological diagnosis of endometrial clear cell carcinoma (ECCC). Immunohistochemical staining of TFPI2 in 55 endometrial carcinomas was evaluated at Nara Medical University Hospital. Thirteen ECCC samples were included as cases and 42 samples were included as a control (endometrioid carcinoma grade 1, 11 cases; grade 2, 11 cases; grade 3, 10 cases; serous carcinoma, 10 cases). The mean ± SD TFPI2 histoscore for diagnosing ECCC was 115.4 ± 87.9, which was significantly higher than that of non-ECCC (21.3 ± 45.9, P = 0.002). The best TFPI2 histoscore value obtained from the analyses of receiver operating characteristic curves for immunohistochemical diagnosis of ECCC was 15. With TFPI2 histoscores ≥15.0 as positive and <15.0 as negative, all 13 ECCC cases (100%) were positive for TFPI2, whereas 11 (26.2%) non-ECCC cases were positive for TFPI2. The sensitivity and specificity of TFPI2 for diagnosing ECCC were 100% and 73.8%, respectively. TFPI2 is expressed in ECCC and is useful for histopathological diagnosis.

Correlation of clinicopathological and prognostic characteristics between endometriosis-associated and primary ovarian cancer.

BACKGROUND: The main aim of this study was to establish the clinicopathological and prognostic correlations between endometriosis-associated and non-endometriosis-associated primary ovarian cancer, with a view to providing a reference guide for revision of diagnostic criteria for malignant transformation of endometriosis. METHODS: Clinicopathological and follow-up data of 174 patients with clear cell and endometrial ovarian cancer were retrospectively extracted. Cases were divided into endometriosis-associated and non-endometriosis-associated primary ovarian cancer for comparative analysis of clinicopathological characteristics and prognosis. RESULTS: Average age and post-menopausal rate in the endometriosis-associated ovarian cancer group were lower relative to the primary ovarian cancer group (P < 0.05). Body mass index, age at menopause, operation history, dysmenorrhea, complications, tumor size, tumor side, ascites, CA125, HE4, CA19.9, stage, differentiation, expression of ER, PR, P53, P16, Ki67, MMR, HNF-1ß and Napsin A were not significantly different between the groups (P > 0.05). Furthermore, rates of resistance to platinum chemotherapy, relapse, progression-free survival and overall survival were comparable between the two groups (P > 0.05). CONCLUSION: Endometriosis-associated and primary ovarian cancers of the same pathological type are speculated to be homologous in terms of origin from malignant transformation of endometriosis. It may therefore be necessary to revise the diagnostic criteria for ovarian endometriosis malignancy.

Prognosis and adjuvant chemotherapy for patients with malignant peritoneal cytology in early-stage non-endometrioid endometrial cancer.

OBJECTIVE: To investigate the influence of malignant peritoneal cytology (MPC) on the prognosis of early-stage patients with endometrial clear cell carcinoma(CCC) and serous carcinoma(SC), and the value of chemotherapy in their treatment. METHODS: A retrospective observational cohort study was conducted by querying the National Cancer Institute's Surveillance, Epidemiology, and End Results Program from 2010 to 2019. Women with early-stage CCC and SC with available peritoneal cytology results were enrolled. Propensity score matching(PSM) and propensity score inverse probability of treatment weighting (IPTW) was used to balance the measured covariates in each sub-cohort. RESULTS: A total of 3,616 eligible patients were included, and 368 patients had MPC (10.2%). Women with MPC were more likely to receive postoperative chemotherapy (OR 2.033; 95%CI 1.589-2.602). In PSM model, MPC had worse overall survival(OS) and cancer-specific survival (CSS) (All,p < 0.001). The 5-year OS rates were 56.5% for women with MPC and 74.4% for those with negative peritoneal cytology, and the 5-year CSS rates were 60.8% versus 80.0%(All, p < 0.0001). In the subgroup analyses, MPC was associated with decreased OS and CSS in serous, clear cell histology group, and stage IA cases(All,p < 0.001), but not for stage IB or stage II disease. In multivariate analysis, chemotherapy improved the prognosis of patients with MPC(OS:p = 0.005; CSS:p = 0.010). Additionally, in stage IA subgroup, chemotherapy improved survival outcomes in patients with MPC(OS:P = 0.025; CSS:P = 0.038), in NPC patients, however, chemotherapy was a good prognostic factor for OS (P = 0.001) but not for CSS(P = 0.300). CONCLUSION: MPC was a prognostic factor for decreased survival in early-stage endometrial CCC and SC, and those with MPC could further benefit from chemotherapy.

Prognostic impact of molecular profiles and molecular signatures in clear cell ovarian cancer.

OBJECTIVE: Ovarian Clear cell carcinomas (OCCC) are characterized by low response to chemotherapy and a poor prognosis in advanced stages. Several studies have demonstrated that OCCC are heterogenous entities. We have earlier identified four molecular profiles based on the mutational status of ARID1A and PIK3CA. In this study we aimed to examine the association between molecular profiles, Tumor Mutational Burden (TMB), and molecular signatures with the clinical outcome in OCCC METHODS: We identified 55 OCCC cases with corresponding data and biological tissue samples in the Danish Gynecological Cancer Database during 2005-2016. Mutational profiling and TMB were performed using the Oncomine Tumor Mutational Load Assay. Chi-square and Cox regression analyses were used. P-values < 0.05 were considered statistically significant. RESULTS: Mutations in the PIK3CA gene (p=0.04) and low TMB (p=0.05) were associated with disease progression. In multivariate analyses adjusted for stage, patients with tumor mutations in the ARID1A and/or PIK3CA genes had a significantly impaired Progression Free Survival (PFS) and Overall Survival (OS) compared to patients who were wildtype ARID1A and PIK3CA (undetermined subgroup) (HR= 5.42 and HR= 2.77, respectively). High TMB status was associated with an improved PFS (HR= 0.36) and OS (HR= 0.46). A trend towards an improved PFS in patients with APOBEC enrichment was observed (HR 0.45). CONCLUSION: TMB-High was associated with decreased risk of progression and with an improved PFS and OS. Furthermore, OCCC with mutations in either ARID1A and/or PIK3CA genes had a significantly impaired prognosis compared to the undetermined subgroup in stage adjusted analyses.

Mixed clear cell/endometrioid and clear cell/serous carcinoma of the uterus are clinicopathologically similar to pure clear cell carcinoma: An NRG Oncology/Gynecologic Oncology Group (GOG-210) study of 311 women.

OBJECTIVES: Clear cell carcinoma is a high-risk subtype of endometrial cancer. Some patients have a mixture of clear cell carcinoma with other histologic types (endometrioid or serous) or cannot be neatly assigned to one of these types. Protocol GOG-8032 within GOG-210 was designed to determine whether these tumors differ from pure clear cell carcinoma in stage at diagnosis, initial pattern of spread, or patient survival. METHODS: The term "mixed" was applied to tumors with multiple identifiable components, and "indeterminate" was applied to tumors with features intermediate between different histologic types. Three hundred eleven women with pure, mixed, or indeterminate clear cell carcinoma were identified in a larger cohort of patients undergoing hysterectomy for endometrial cancer in GOG-210. Histologic slides were centrally reviewed by expert pathologists. Baseline and follow-up data were analyzed. RESULTS: One hundred thirty-six patients had pure clear cell carcinoma and 175 had a mixed or indeterminate clear cell pattern. Baseline clinicopathologic characteristics were similar except for a small difference in age at presentation. Univariate survival analysis confirmed the significance of typical endometrial cancer prognostic factors. Patients in the mixed categories had disease-free and overall survival similar to pure clear cell carcinoma, but the indeterminate clear cell/endometrioid group had longer survival. CONCLUSION: In clear cell endometrial cancer, the presence of a definite admixed endometrioid or serous component did not correlate with a significant difference in prognosis. Patients whose tumors had indeterminate clear cell features had better prognosis. Some of these tumors may be endometrioid tumors mimicking clear cell carcinoma.

Genomic landscapes of ovarian clear cell carcinoma from latin countries reveal aberrations linked to survival and progression.

BACKGROUND: Ovarian clear cell carcinomas (OCCCs) are rare, aggressive and chemoresistant tumors. Geographical and ethnic differences in the incidence of OCCC have been reported with a higher incidence in Asiatic countries. There is a paucity of information regarding OCCC in Latin America (LA) and other countries. METHODS: Here, we characterized two cohorts of 33 patients with OCCC from LA (24 from Brazil and 9 from Costa Rica) and a cohort of 27 patients from Spain. Genomic analysis was performed for 26 OCCC using the OncoScan platform. Tumors were classified according to their genomic landscapes into subgroups. Clinical parameters were related to the frequency of genomic aberrations. RESULTS: The median overall survival (OS) was not significantly different between the cohorts. Genomic landscapes were characterized by different homologous recombination deficiency (HRD) levels. No difference in the distribution of genomic landscapes profiles was detected between patients from the different cohorts. OCCCs with MYC-amplified tumors harboring a concomitant loss of a region in chromosome 13q12-q13 that includes the BRCA2 gene had the longest OS. In contrast, patients carrying a high number (> 30) of total copy number (CN) aberrations with no concomitant alterations in MYC and BRCA2 genes presented the shortest OS. Furthermore, amplification of the ASH1L gene was also associated with a shorter OS. Initial-stage OCCCs with early progression were characterized by gains in the JNK1 and MKL1 genes. CONCLUSIONS: Our results provide new data from understudied OCCC populations and reveal new potential markers for OCCCs.